Wide-body arrow having tapered tail

ABSTRACT

A cylindrical carbon fiber arrow shaft formed with an increased external diameter of 0.380 inches. This arrow shaft is formed with an axial bore which has a first internal diameter throughout a substantial portion of the shaft length, and a second, smaller, internal diameter throughout the fletching end of the arrow. The second internal diameter corresponds to the internal diameter of standard arrows having external diameters of 0.295 inches. Using this standard internal diameter at the fletching-end of the arrow, standard nooks may be used without the need for any spacer or insert, thereby decreasing fletching-end weight significantly and providing for the proper and more desired location of the center of gravity forward on the arrow.

RELATED APPLICATION

The present application is a Divisional of U.S. patent application Ser.No. 14/486,961 filed Sep. 15, 2014, which is a Divisional of U.S. patentapplication Ser. No. 13/909,888 filed Jun. 4, 2013, and which is nowU.S. Pat. No. 8,834,658, which is a Divisional of U.S. patentapplication Ser. No. 12/943,870 filed Nov. 10, 2010, and which is nowU.S. Pat. No. 8,496,548.

FIELD OF THE INVENTION

The present invention relates generally to archery. The presentinvention is more particularly, though not exclusively, useful as animproved archery arrow having improved weight distribution andaerodynamics.

BACKGROUND OF THE INVENTION

Archery arrows have been in use for centuries. Over this timer period,significant improvements have been made in the design of the arrows. Forinstance, the materials used for arrows have evolved from ancient arrowsmade of wood to modern arrows fabricated using lightweight high strengthcarbon fiber composites. Also, the Fletching, or Finning, has evolvedfrom a standard X-shape feather to an aerodynamic three-tab design whichminimizes contact with the bow and improves accuracy. Improvements havealso been made to the arrow head to improve aerodynamics and to the nockto decrease weight, for instance.

A recent trend in the arrow industry is to provide an arrow having awider diameter shaft. Typical arrows have had a standard external shaftdiameter of 0.295 inches which has provided for a reasonably rigid arrowmade from today's materials. However, a thicker arrow having an externalshaft diameter of 0.380 has been developed for certain archeryapplications.

However, with the wider diameter of these thicker arrows comes anincrease in weight and aerodynamic drag caused by the largercross-section. In order to minimize the effects of the larger diameteron the arrow performance, the industry has taken steps to minimizeweight of the arrow. For instance, some manufacturers have providedadaptors which can allow the archer to use standard diameter nooks.However, in order to use the smaller diameter flocks, a transitionalsleeve, or taper, must be inserted between the shaft and the nook.Unfortunately, this added insert provides excess weight at the fletchingend of the arrow. This is particularly so when using carbon-fiber arrowswhere the weight of the arrow is small compared to the weight of the tipand nook.

In light of the above, it would be advantageous to provide an arrowhaving increased strength and decreased drag which is also lightweight.It would also be advantageous to provide an arrow capable of usingstandard nooks without having to add weight-increasing adapters andinserts.

SUMMARY OF THE INVENTION

The present invention includes a cylindrical carbon fiber arrow shaftformed with an increased external diameter of 0.380 inches. This arrowshaft is formed with an axial bore which has a first internal diameterthroughout a substantial portion of the shaft length, and a second,smaller, internal diameter throughout the fletching end of the arrow.The second internal diameter corresponds to the internal diameter ofstandard arrows having external diameters of 0.295 inches. Using thisstandard internal diameter at the fletching-end of the arrow, standardnooks may be used without the need for any spacer or insert, therebydecreasing fletching-end weight significantly and providing for theproper and more desired location of the center of gravity forward on thearrow.

The dual interior-diameter design of the arrow of the present inventionis accomplished using a cylindrical mandrel having two externaldiameters. The first mandrel diameter corresponds to the portion of thearrow shaft having the external diameter of 0.380 inches, and the secondmandrel diameter corresponds to the standard nook dimensions.

The carbon fiber shaft is formed on the mandrel. With the aid ofreleasing agents, the mandrel is removed leaving a tubular shaft havinga decreased internal diameter at the fletching end of the arrow. A taperis formed at the end of the arrow to provide for a smooth transitionbetween the arrow shaft and the smaller-diameter nook. A nook is theninserted, the fletching is applied, and a tip is installed to provide ahigh strength, low weight archery arrow having less mass than comparablearrows.

DESCRIPTION OF THE DRAWING

The objects, features, and advantages of the method according to theinvention will be more clearly perceived from the following detaileddescription, when read in conjunction with the accompanying drawing, inwhich:

FIG. 1 is a side view of a PRIOR ART arrow showing the small exteriordiameter and placement of the tip, fletching and nook, and an exemplarycenter-of-gravity;

FIG. 2 is a detailed view of a standard nock as used in conjunction withsmall exterior diameter arrows and showing the insert and bow receiver:

FIG. 3 is a side view of an arrow of the present invention having awider exterior diameter and having a tip, fletching, nock, and formedwith a tapered portion of the carbon fiber body into which the nook isinserted, as well as an exemplary center-of-gravity;

FIG. 4 is a cross-sectional view of the fletching end of the arrow ofthe present invention showing the portion of the arrow having a smallerinternal diameter sized to closely receive a standard nock;

FIG. 5 is a cross-sectional view of the arrow of the present inventionshowing the placement of a mandrel having two diameters positioned toform an arrow body having a first diameter, and a fletching portionhaving a smaller diameter, and also showing the formation of the taperby removing a portion of the carbon fiber materials, such as bygrinding; and

FIG. 6 is a cross-section of the fletching end of an arrow showing thefirst internal body diameter and the second smaller internal bodydiameter, and the transition stop, as well as the nook receptor formedto receive a standard nock

DETAILED DESCRIPTION

Referring now to FIG. 1, a side view of a PRIOR ART arrow 10 is showndetailing the small exterior diameter 14 and placement of the tip 16,fletching 18 and nock 20. As is known in the industry, the length of thearrow, the weight of the tip and fletching determines in large part thelocation of the center-of-gravity 30 of the arrow. It is also known inthe industry that the placement of the center of gravity in positionsalong the length of an arrow can significantly affect the flight of thearrow.

The nock can also affect the position of the center of gravity. Forinstance, in arrows having very low weights, the addition of the nock atthe end of the arrow can bring the center of gravity away from the tip,sometimes resulting in a less-than-optimum placement.

FIG. 2 is a detailed view of a standard nock 20 as used in conjunctionwith small exterior diameter arrows 10. Nock 20 includes an insert 24leading through a stop 26 to a body 28 formed with a bow receiver 30.The diameter 32 of the insert 24 is such that the insert is closely andsecurely received in the bore of an arrow shaft. Additionally, anadhesive may be applied when inserting the insert into the shaft toprovide added strength for the retention of the nook.

Referring now to FIG. 3, a side view of arrow 100 of the presentinvention has a shaft 102 having a wider exterior diameter 104. In apreferred embodiment, the exterior diameter is 0.380 inches, however, itis to be appreciated that other diameters could be contemplated withoutdeparting from the present invention.

Arrow 100 includes a tip 106 which is typically a weighty metallicmaterial, such as steel, and can be formed with different shapes forspecific uses, such as target shooting, hunting, etc. Retching 108 isattached to the exterior of body 102 as is known in the art, and nook 20is inserted into the fletching end of the shaft body 102.

Arrow shaft 102 is formed with an axial bore (shown in FIG. 4) andformed with tapered portion 110 which has an interior diameter whichcorresponds to the interior diameter of standard 0.295 inch arrows.Using this standard internal diameter at the fletching-end of the arrow,standard nooks may be used without the need for any spacer or insert,thereby decreasing fletching-end weight significantly and providing forthe proper and more desired location of the center of gravity forward onthe arrow.

Arrow 100 is shown having an exemplary center-of-gravity 114 which as isknown in the art, may be adjusted along the length of the shaft 102 byadjusting the weights of the tip 106, fletching 108 and nock 20. Also,the position of the center of gravity may be affected by the shortening,or cutting, of the length of the arrow.

FIG. 4 is a cross-sectional view of the arrow 100 of the presentinvention taken along line 4-4 of FIG. 3, and showing the portion of thearrow 100 having a smaller internal diameter sized to closely receive astandard nook 20. Specifically, shaft 102 is formed with a bore 116having a transition at the nock-end of the arrow to a smaller diameterbore sized to receive the insert 24 of nook 20.

A tapered section 110 of body 102 transitions the arrow from the largerdiameter of 0.380 inches, to a smaller diameter, such as 0.295 inches tocorrespond to the diameter of the nook 20. The length of the taper andthe angle of the taper can vary depending on the manufacturing of thearrow 100 without departing from the spirit of the present invention.

An example of a typical manufacturing method is depicted in FIG. 5.Carbon fiber manufacturing is known in the art, and includes thewrapping of carbon fibers around a mandrel which is then heated andformed into the desired article of manufacture. For the presentinvention, a cross-sectional view of the arrow 100 of the presentinvention shows the use of a mandrel 150 having two sections 152 and154. Section 152 has a diameter 156, and section 154 has a diameter 158.These diameters 156 and 158 cooperate to form an arrow body 102 having afirst larger diameter 156, and a fletching portion having a smallerdiameter 158 which corresponds to the standard nock dimensions.

Tapered section 110 is formed on the fletching end of body 102 byremoving a portion 120 of the carbon fiber materials as shown by dashedlines. The removal of the material of body 102 may be accomplished usinga variety of techniques, such as by grinding as is known in the art.

FIG. 6 is a cross-section of the fletching end of arrow 100 showing thefirst internal body diameter 134 and the second smaller internal bodydiameter 136. Body 102 is formed with a transition stop 130 betweendiameters 134 and 136. By decreasing the diameter 136 of body 102, thereis sufficient strength in the materials of the shaft so that nook 20(not shown this Figure) is securely received in the shaft. Moreover, byforming the diameter 136 of inlet 132 to receive a standard lightweightnook, the weight of the arrow assembly is decreased, as well as making amore cost-effective arrow.

The arrow of the present invention exhibits improved aerodynamics, lowermass, and has a better weight distribution than other large diameterarrows which require the use of heavy transition pieces, or super-sizednocks. The use of the standard nook without any additional hardwareprovides the arrow of the present invention with a significant advantageover other arrows.

We claim:
 1. A method of manufacturing an arrow shaft, comprising:providing a mandrel having a first cylindrical portion having a firstdiameter and a second cylindrical portion having a second diameter:wrapping carbon fiber about said mandrel to form an arrow shaft with atip end and a fletching end having a first internal diameter adjacentsaid tip end and a second internal diameter adjacent said fletching end,wherein said first internal diameter has said first diameter and saidsecond internal diameter has said second diameter; impregnating saidarrow shaft with an epoxy resin; removing said arrow shaft from saidmandrel; and forming a taper on said fletching end of said arrow shaftby removing material from said fletching end.
 2. The method ofmanufacturing an arrow shaft of claim 1, wherein said first diameter islarger than said second diameter.
 3. The method of manufacturing anarrow shaft of claim 1, wherein said arrow shaft has a uniform externaldiameter.
 4. The method of manufacturing an arrow shaft of claim 1,wherein heat is applied to said carbon fiber and said epoxy resin toform said arrow shaft.
 5. The method of manufacturing an arrow of claim1, wherein said taper is formed after heat has been applied to saidcarbon fiber and said epoxy resin.
 6. The method of manufacturing anarrow of claim 5, wherein said taper starts at a predetermined distanceahead of said fletching end and becomes progressively smaller untilreaching a diameter, approximately equal to the external diameter of anook body, at said fletching end.
 7. A method of manufacturing an arrowshaft, comprising: providing a mandrel having a first cylindricalportion having a first diameter and a second cylindrical portion havinga second diameter; wrapping carbon fiber about said mandrel to form anarrow shaft having a uniform external diameter with a tip end and a nockend, a first internal bore having said first diameter adjacent said tipend, and a second internal bore having said second diameter adjacentsaid fletching end; impregnating said carbon fiber with an epoxy resin;heating said carbon fiber, epoxy resin and mandrel; cooling said carbonfiber, epoxy resin and mandrel; removing said carbon fiber and epoxyresin from said mandrel; and removing material on said fletching end ofsaid arrow shaft to form a taper on said fletching end of said arrowshaft.
 8. The method of manufacturing of claim 7, wherein said firstdiameter is greater than said second diameter.
 9. The method ofmanufacturing an arrow of claim 7, wherein said taper starts at apredetermined distance ahead of said fletching end and becomesprogressively smaller until reaching a diameter, approximately equal tothe external diameter of a nook body, at said fletching end.
 10. Amethod of manufacturing an arrow shaft, comprising: providing a mandrelhaving a first cylindrical portion having a first diameter and a secondcylindrical portion having a second diameter; wrapping carbon fiberabout said mandrel; impregnating said carbon fiber with an epoxy resin;removing said carbon fiber with said epoxy resin from said mandrel; andremoving material from said carbon fiber and said epoxy resin to form atapered end.
 11. The method of manufacturing an arrow of claim 10,wherein said step of removing material from said carbon fiber and saidepoxy resin to form a tapered end comprises grinding or cutting.